VM: New calling convention for generated code.

runtime/vm/code_patcher.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 // Class for patching compiled code.
 
 #ifndef VM_CODE_PATCHER_H_
 #define VM_CODE_PATCHER_H_
 
 #include "vm/allocation.h"
 #include "vm/native_entry.h"
 
 namespace dart {
 
 // Forward declaration.
 class Array;
 class Code;
 class ExternalLabel;
 class Function;
 class ICData;
 class RawArray;
+class RawCode;
 class RawFunction;
 class RawICData;
 class RawObject;
 class String;
 
 
 // Stack-allocated class to create a scope where the specified region
 // [address, addresss + size] has write access enabled. This is used
 // when patching generated code. Access is reset to read-execute in
 // the destructor of this scope.
 class WritableInstructionsScope : public ValueObject {
  public:
   WritableInstructionsScope(uword address, intptr_t size);
   ~WritableInstructionsScope();
 
  private:
   const uword address_;
   const intptr_t size_;
 };
 
 
 class CodePatcher : public AllStatic {
  public:
   // Dart static calls have a distinct, machine-dependent code pattern.
 
   // Patch static call before return_address in given code to the new target.
   static void PatchStaticCallAt(uword return_address,
                                 const Code& code,
-                                uword new_target_address);
+                                const Code& new_target);
 
   // Patch instance call before return_address in given code to the new target.
   static void PatchInstanceCallAt(uword return_address,
                                   const Code& code,
-                                  uword new_target_address);
+                                  const Code& new_target);
 
   // Patch entry point with a jump as specified in the code's patch region.
-  static void PatchEntry(const Code& code);
+  static void PatchEntry(const Code& code, const Code& new_code);
 
   // Restore entry point with original code (i.e., before patching).
   static void RestoreEntry(const Code& code);
 
   // Has the entry been patched?
   static bool IsEntryPatched(const Code& code);
 
-  // Returns true if the code can be patched with a jump at beginning (checks
-  // that there are no conflicts with object pointers). Used in ASSERTs.
-  static bool CodeIsPatchable(const Code& code);
-
   // Return the target address of the static call before return_address
   // in given code.
-  static uword GetStaticCallTargetAt(uword return_address, const Code& code);
+  static RawCode* GetStaticCallTargetAt(uword return_address, const Code& code);
 
   // Get instance call information.  Returns the call target and sets each
   // of the output parameters ic_data and arguments_descriptor if they are
   // non-NULL.
-  static uword GetInstanceCallAt(uword return_address,
-                                 const Code& code,
-                                 ICData* ic_data);
+  static RawCode* GetInstanceCallAt(uword return_address,
+                                    const Code& code,
+                                    ICData* ic_data);
 
   // Return target of an unoptimized static call and its ICData object
   // (calls target via a stub).
   static RawFunction* GetUnoptimizedStaticCallAt(uword return_address,
                                                  const Code& code,
                                                  ICData* ic_data);
 
   static intptr_t InstanceCallSizeInBytes();
 
-  static void InsertCallAt(uword start, uword target);
+  // TODO(fschneider): Rename if inly used for lazy-deopt.
+  static void InsertDeoptimizationCallAt(uword start, uword target);
 
   static RawObject* GetEdgeCounterAt(uword pc, const Code& code);
 
   static void PatchPoolPointerCallAt(uword return_address,
                                      const Code& code,
-                                     uword new_target);
+                                     const Code& new_target);
 
-  static uword GetNativeCallAt(uword return_address,
-                               const Code& code,
-                               NativeFunction* target);
+  static RawCode* GetNativeCallAt(uword return_address,
+                                  const Code& code,
+                                  NativeFunction* target);
 
   static void PatchNativeCallAt(uword return_address,
                                 const Code& code,
                                 NativeFunction target,
                                 const Code& trampoline);
 };
 
 }  // namespace dart
 
 #endif  // VM_CODE_PATCHER_H_